1. Field of the Invention
The present invention relates to a solar battery module and more particularly, to a solar battery roof and a mounting method thereof realizing simplification of installing and securing methods.
2. Related Background Art
Solar batteries have popularly been used heretofore as clean and non-exhaustive energy supply sources and various research and development has been conducted on the solar cells or batteries themselves. Further, development is active on solar battery modules well suited to installation at a variety of places, for example, on the ground and on the roof.
Especially, in terms of installation on the roof, development of combination roofing material and solar battery module, which can also function as a roofing material, is useful also in respect of reduction of cost for spread of solar battery in the future.
An example of the solar battery module suited to the existing roof construction methods is the solar battery module shown in FIG. 8 and FIG. 9, which is described in Japanese Laid-open Patent Application No. 7-211932. FIG. 8 is a cross-sectional view obtained when the central part of the solar battery module is cut vertically in the direction from the ridge to the eaves and FIG. 9 is a cross-sectional view obtained when an edge part of the solar battery module is cut laterally in the direction perpendicular to the foregoing direction. This example is characterized in that air flow path 8 is formed between sheathing roof board 7 and solar battery module 13 and in that heat of the solar battery module heated to high temperatures is conducted to the air flowing in this flow path 8 to heat it up and it is utilized for heating of building.
In FIG. 8 and FIG. 9, junction boxes 10 are provided on the opposite surface (which will be referred to as a back surface) to the light receiving surface of the solar battery module 13, electric output line 11 is drawn out of each junction box 10, and connector 12 is attached to the end thereof to be electrically connected to an adjacent solar battery module.
An example of the solar battery module 13 is fabricated in such a way that an amorphous silicon solar battery is formed on a stainless steel substrate, a translucent resin film is put on the light receiving surface side, a metal reinforcing sheet is put on the back surface side, and the laminate is resin-sealed with a translucent resin. This solar battery module 13 is bent by folding together with the translucent resin film, translucent resin, and metal reinforcing sheet, thereby being formed in a shape suitable for the batten-seam roof structure as shown in FIG. 9, which is one of the conventional roof construction methods.
The installation and securing sequence is as follows. For forming the space 8 between the sheathing roof board 7 and the solar battery module 13, spacer members 14a, 14b are fixed by unillustrated nails to the sheathing roof board 7, then the solar battery module 13 is mounted thereon, and retaining clip 15 is fixed by drill screw 16, thereby installing and securing the solar battery module 13. At this time, the distance between the spacer members 14a is 455 mm in the case of the conventional shaku (unit of length) construction method or 500 mm in the case of the meter construction method. Reference numeral 17 designates the batten, which functions as a flashing.
When exposed to the sunlight, the solar battery module 13 is heated to high temperatures, approximately 80xc2x0 C. The air flows in the flow path of the space 8 on the back surface side of the solar battery module 13 and the air rises up to the ridge as being heated by heat conduction from the solar battery module 13 and is taken into the room to be used for heating.
In the above conventional technology, the spacer members 14a and 14b must be installed and fixed at accurate positions relative to the solar battery module 13. Namely, as shown in FIG. 9, the spacer members must be installed and fixed so as to accurately support the both edge portions of the solar battery module 13 having the width of about 455 mm to 500 mm. It is, however, very troublesome to carry out the installing and fixing works of the spacer members 14a and 14b at the accurate positions in the working site on the roof of poor foothold.
Means for solving the above problem is achieved by a solar battery module wherein a photovoltaic element is fixed on a reinforcing sheet, a plurality of junction boxes are provided for drawing power out of the photovoltaic element to the outside, first spacer members higher than the junction boxes are placed along two opposite sides of the reinforcing sheet, and a second spacer member is placed between the plurality of junction boxes.
When the solar battery module is applied to the roof, the roof is so constructed that the first spacer members are fixed on a roof substrate material, the space defined between the roofing material and the roof substrate material is open to the outside air at the eaves, and the space is in communication with the inside of house at the ridge.